net.sf.saxon.expr.instruct

## Class FixedAttribute

- java.lang.Object
- - net.sf.saxon.expr.Expression
  - - net.sf.saxon.expr.instruct.Instruction
    - - net.sf.saxon.expr.instruct.SimpleNodeConstructor
      - - net.sf.saxon.expr.instruct.AttributeCreator
        - - net.sf.saxon.expr.instruct.FixedAttribute

- All Implemented Interfaces:
    Serializable, SourceLocator, LocationProvider, SaxonLocator, TailCallReturner, ValidatingInstruction, InstructionInfo, Locator

      public final class FixedAttribute
      extends AttributeCreator

  An instruction derived from an xsl:attribute element in stylesheet, or from an attribute constructor in XQuery. This version deals only with attributes whose name is known at compile time. It is also used for attributes of literal result elements. The value of the attribute is in general computed at run-time.
  See Also:
    Serialized Form

- - ### Field Summary

    - ### Fields inherited from class net.sf.saxon.expr.instruct.SimpleNodeConstructor

      `select`

    - ### Fields inherited from class net.sf.saxon.expr.Expression

      `EFFECTIVE_BOOLEAN_VALUE, EVALUATE_METHOD, EVENT_FEED_METHOD, INHERITED_CONTEXT, INSPECTION_CONTEXT, ITEM_FEED_METHOD, ITERATE_METHOD, locationId, MAX_SEQUENCE_LENGTH, MAX_STRING_LENGTH, NAVIGATION_CONTEXT, NODE_VALUE_CONTEXT, PROCESS_METHOD, PUSH_SELECTION, staticProperties, UNBOUNDED_LOWER, UNBOUNDED_UPPER, W3C_CONSUMING, W3C_FREE_RANGING, W3C_GROUP_CONSUMING, W3C_MOTIONLESS, WATCH_METHOD`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `FixedAttribute(NodeName nodeName, int validationAction, SimpleType schemaType)` Construct an Attribute instruction

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `checkPermittedContents(SchemaType parentType, StaticContext env, boolean whole)` Check that any elements and attributes constructed or returned by this expression are acceptable in the content model of a given complex type.
    `Expression` | `copy()` Copy an expression.
    `NodeInfo` | `evaluateItem(XPathContext context)` Evaluate as an expression.
    `NodeName` | `evaluateNodeName(XPathContext context)` Run-time method to compute the name of the node being constructed.
    `void` | `explain(ExpressionPresenter out)` Diagnostic print of expression structure.
    `NodeName` | `getAttributeName()`
    `int` | `getAttributeNameCode()` Get the name pool name code of the attribute to be constructed
    `int` | `getCardinality()` Determine the static cardinality of the expression.
    `ExpressionCompiler` | `getExpressionCompiler()` Return the compiler of the FixedAttribute expression
    `int` | `getInstructionNameCode()` Get the name of this instruction (return 'xsl:attribute')
    `void` | `localTypeCheck(ExpressionVisitor visitor, ExpressionVisitor.ContextItemType contextItemType)` Method to perform type-checking specific to the kind of instruction
    `void` | `setSelect(Expression select, Configuration config)` Set the expression defining the value of the attribute.

    - ### Methods inherited from class net.sf.saxon.expr.instruct.AttributeCreator

      `computeSpecialProperties, getItemType, getOptions, getSchemaType, getValidationAction, processValue, setNoSpecialChars, setOptions, setRejectDuplicates, setSchemaType, setValidationAction, validateOrphanAttribute`

    - ### Methods inherited from class net.sf.saxon.expr.instruct.SimpleNodeConstructor

      `checkContent, computeCardinality, createsNewNodes, getContentExpression, getStreamingAdjunct, iterate, iterateSubExpressionInfo, iterateSubExpressions, optimize, processLeavingTail, promoteInst, replaceSubExpression, simplify, typeCheck`

    - ### Methods inherited from class net.sf.saxon.expr.instruct.Instruction

      `assembleParams, assembleTunnelParams, dynamicError, evaluateAsString, getConstructType, getExpressionName, getImplementationMethod, getInstructionName, getIteratorFromProcessMethod, getSourceLocator, isXSLT, process, promote`

    - ### Methods inherited from class net.sf.saxon.expr.Expression

      `addToPathMap, adoptChildExpression, checkForUpdatingSubexpressions, computeDependencies, computeStaticProperties, doPromotion, dynamicError, effectiveBooleanValue, evaluatePendingUpdates, explain, getColumnNumber, getColumnNumber, getContainer, getDependencies, getEvaluationMethod, getExecutable, getHostLanguage, getIntegerBounds, getIntrinsicDependencies, getLineNumber, getLineNumber, getLocationId, getLocationProvider, getObjectName, getProperties, getProperty, getPublicId, getSlotsUsed, getSpecialProperties, getStreamability, getSystemId, getSystemId, hasVariableBinding, implementsStaticTypeCheck, isSubtreeExpression, isUpdatingExpression, isVacuousExpression, iterateEvents, markTailFunctionCalls, resetLocalStaticProperties, setContainer, setEvaluationMethod, setFiltered, setFlattened, setLocationId, staticTypeCheck, suppressValidation, toPattern, toStreamingPattern, toString, typeError`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

    - ### Methods inherited from interface javax.xml.transform.SourceLocator

      `getColumnNumber, getLineNumber, getPublicId, getSystemId`

- - ### Constructor Detail

    - #### FixedAttribute

          public FixedAttribute(NodeName nodeName,
                        int validationAction,
                        SimpleType schemaType)

      Construct an Attribute instruction
      Parameters:
        `nodeName` - Represents the attribute name
        `validationAction` - the validation required, for example strict or lax
        `schemaType` - the schema type against which validation is required, null if not applicable of the instruction - zero if the attribute was not present

  - ### Method Detail

    - #### getInstructionNameCode

          public int getInstructionNameCode()

      Get the name of this instruction (return 'xsl:attribute')
      Overrides:
        `getInstructionNameCode` in class `Instruction`
      Returns:
        a code identifying the instruction: typically but not always the fingerprint of a name in the XSLT namespace

    - #### getAttributeName

          public NodeName getAttributeName()

    - #### setSelect

          public void setSelect(Expression select,
                       Configuration config)

      Set the expression defining the value of the attribute. If this is a constant, and if validation against a schema type was requested, the validation is done immediately.
      Overrides:
        `setSelect` in class `SimpleNodeConstructor`
      Parameters:
        `select` - The expression defining the content of the attribute
        `config` - The Saxon configuration

    - #### localTypeCheck

          public void localTypeCheck(ExpressionVisitor visitor,
                            ExpressionVisitor.ContextItemType contextItemType)
                              throws XPathException

      Description copied from class: `SimpleNodeConstructor`
      Method to perform type-checking specific to the kind of instruction
      Specified by:
        `localTypeCheck` in class `SimpleNodeConstructor`
      Parameters:
        `visitor` - an expression visitor
        `contextItemType` - the static type of the context item
      Throws:
        `XPathException` - if a type error is detected

    - #### getAttributeNameCode

          public int getAttributeNameCode()

      Get the name pool name code of the attribute to be constructed
      Returns:
        the attribute's name code

    - #### getCardinality

          public int getCardinality()

      Description copied from class: `Expression`
      Determine the static cardinality of the expression. This establishes how many items there will be in the result of the expression, at compile time (i.e., without actually evaluating the result.
      Overrides:
        `getCardinality` in class `Expression`
      Returns:
        one of the values Cardinality.ONE_OR_MORE, Cardinality.ZERO_OR_MORE, Cardinality.EXACTLY_ONE, Cardinality.ZERO_OR_ONE, Cardinality.EMPTY. This default implementation returns ZERO_OR_MORE (which effectively gives no information).

    - #### copy

          public Expression copy()

      Copy an expression. This makes a deep copy.
      Specified by:
        `copy` in class `Expression`
      Returns:
        the copy of the original expression

    - #### evaluateNodeName

          public NodeName evaluateNodeName(XPathContext context)

      Description copied from class: `SimpleNodeConstructor`
      Run-time method to compute the name of the node being constructed. This is overridden for nodes that have a name. The default implementation returns -1, which is suitable for unnamed nodes such as comments
      Overrides:
        `evaluateNodeName` in class `SimpleNodeConstructor`
      Parameters:
        `context` - the XPath dynamic evaluation context
      Returns:
        the name pool nameCode identifying the name of the constructed node

    - #### checkPermittedContents

          public void checkPermittedContents(SchemaType parentType,
                                    StaticContext env,
                                    boolean whole)
                                      throws XPathException

      Check that any elements and attributes constructed or returned by this expression are acceptable in the content model of a given complex type. It's always OK to say yes, since the check will be repeated at run-time. The process of checking element and attribute constructors against the content model of a complex type also registers the type of content expected of those constructors, so the static validation can continue recursively.
      Overrides:
        `checkPermittedContents` in class `Expression`
      Parameters:
        `parentType` - the "given complex type": the method is checking that the nodes returned by this expression are acceptable members of the content model of this type
        `env` - the static context
        `whole` - if true, we want to check that the value of this expression satisfies the content model as a whole; if false we want to check that the value of the expression is acceptable as one part of the content
      Throws:
        `XPathException` - if the value delivered by this expression cannot be part of the content model of the given type

    - #### evaluateItem

          public NodeInfo evaluateItem(XPathContext context)
                                throws XPathException

      Description copied from class: `SimpleNodeConstructor`
      Evaluate as an expression.
      Overrides:
        `evaluateItem` in class `SimpleNodeConstructor`
      Parameters:
        `context` - The context in which the expression is to be evaluated
      Returns:
        the node or atomic value that results from evaluating the expression; or null to indicate that the result is an empty sequence
      Throws:
        `XPathException` - if any dynamic error occurs evaluating the expression

    - #### getExpressionCompiler

          public ExpressionCompiler getExpressionCompiler()

      Return the compiler of the FixedAttribute expression
      Overrides:
        `getExpressionCompiler` in class `Expression`
      Returns:
        the relevant ExpressionCompiler

    - #### explain

          public void explain(ExpressionPresenter out)

      Diagnostic print of expression structure. The abstract expression tree is written to the supplied output destination.
      Specified by:
        `explain` in class `Expression`
      Parameters:
        `out` - the expression presenter used to display the structure

Copyright (c) 2004-2013 Saxonica Limited. All rights reserved.